JP2015063121A - Waterproof ventilation film, waterproof ventilation member having the same, waterproof ventilation structure and waterproof sound-transmitting film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a waterproof ventilation film having air permeability and waterproofness at a level higher than that of conventional ones, and a manufacturing method thereof.SOLUTION: A waterproof ventilation film includes: a non-porous resin film having a plurality of through holes penetrating in a thickness direction; and a solution repellent layer formed on the principal plane of the resin film and having openings each at a location corresponding to each of the plurality of through holes. The through hole extends linearly and has a diameter of 15 μm or less, and the hole density of the through hole in the resin film is 1×10holes/cm-1×10holes/cm. The resin film has the through hole extending in a direction inclined with regard to a direction vertical to the principal plane of the film. The resin film has the through holes extending inclined in different directions in a mixed manner.

Description

  The present invention relates to a waterproof breathable membrane having both waterproof properties and breathability, a waterproof vent member and a waterproof vent structure including the waterproof breathable membrane. The present invention also relates to a waterproof sound-permeable membrane having both waterproof properties and sound-transmitting properties.

  A housing that houses an electronic circuit board such as a vehicle ECU (Electrical Control Unit) and a solar battery control board; a housing that houses electronic equipment or components such as motors, light sources and sensors; electric toothbrushes and shavers An opening for ensuring air permeability between the outside and the inside of the casing is often provided in a casing of such a home appliance; and a casing of an information terminal such as a mobile phone. Thereby, for example, the pressure difference generated between the inside and the outside of the housing can be eliminated or reduced. In the opening, especially when an article contained in the case dislikes water, gas (usually air) is transmitted between the inside and outside of the case to ensure air permeability and the outside of the case. In many cases, a waterproof air-permeable membrane is arranged to prevent water from entering the inside through the opening.

  Separately from this, an opening for transmitting sound between an acoustic part arranged in the casing and the outside of the electronic apparatus is provided in the casing of the electronic apparatus having a voice function such as a mobile phone and a tablet computer. . The sound unit is, for example, a sound generation unit such as a speaker and / or a sound reception unit such as a microphone. Due to the nature of electronic equipment, water intrusion into the housing must be prevented, but the opening for transmitting sound can easily be a path for water to enter. In particular, portable electronic devices are often exposed to rain and water in daily life, and the direction of the opening cannot be fixed in a certain direction that can avoid water (for example, the downward direction in which rain is difficult to blow). The risk of intrusion increases. Therefore, a waterproof sound-permeable membrane that transmits sound between the acoustic unit and the outside and prevents water from entering the housing through the opening from the outside is disposed so as to close the opening.

  An example of the waterproof gas-permeable membrane and the waterproof sound-permeable membrane is a stretched porous membrane having a dispersed structure of innumerable pores generated by stretching. Patent Documents 1 and 2 disclose a waterproof gas-permeable membrane and a waterproof sound-permeable membrane made of a stretched porous membrane of polytetrafluoroethylene (PTFE), respectively. Another example of the waterproof breathable membrane and the waterproof sound-permeable membrane is a non-porous resin film in which a plurality of through-holes penetrating in the thickness direction are formed (see Patent Documents 3 and 4).

JP 2003-318557 A JP 2003-53872 A JP 2012-20279 A JP 2012-195928

  In recent years, there has been a demand for a waterproof breathable membrane that achieves a high level of compatibility between mutually contradictory characteristics of breathability and waterproofness, more specifically, while having high breathability and at the same time achieving high waterproofness. . With such a waterproof breathable membrane, for example, the necessary breathability can be ensured while reducing the vent area, that is, the size of the waterproof vent structure can be reduced. Thereby, for example, the degree of freedom of device design including design is achieved, such as further downsizing and thinning of electronic devices, particularly portable information terminals. In the stretched porous membrane of Patent Document 1, it is difficult to achieve both of these characteristics. In the resin film of patent document 3, the grade which can improve both characteristics is inadequate. On the other hand, with respect to the waterproof sound-permeable membrane, it is required to further improve the sound-permeable characteristics while ensuring high waterproofness.

  One of the objects of the present invention is to provide a waterproof breathable membrane that achieves both breathability and waterproofness at a higher level than before. Another object of the present invention is to provide a waterproof sound-permeable membrane that is excellent in waterproofness and sound-transmitting characteristics.

The waterproof breathable membrane of the present invention corresponds to the non-porous resin film in which a plurality of through holes penetrating in the thickness direction are formed, and the plurality of through holes formed on the main surface of the resin film. And a liquid repellent layer having an opening at the position. The through hole extends linearly and has a diameter of 15 μm or less. The density of the through holes in the resin film is 1 × 10 ³ pieces / cm ² or more and 1 × 10 ⁹ pieces / cm ² or less. The said resin film has the said through-hole extended in the direction inclined with respect to the direction perpendicular | vertical to the main surface of the said resin film. In the resin film, the through holes having different directions extending in an inclined manner are mixed.

  The waterproof breathable member of the present invention comprises the waterproof breathable membrane of the present invention and a support joined to the waterproof breathable membrane.

  The waterproof ventilation structure of the present invention is disposed so as to close the housing having an opening and the opening, and allows water to pass through the opening from the outside while allowing gas to pass between the inside and the outside of the housing. And a waterproof breathable membrane that prevents the intrusion of water. The waterproof breathable membrane is the waterproof breathable membrane of the present invention.

The waterproof sound-permeable membrane of the present invention includes a non-porous resin film in which a plurality of through holes penetrating in the thickness direction are formed, and the plurality of through holes formed on the main surface of the resin film. A liquid repellent layer having an opening at a corresponding position. The through hole extends linearly and has a diameter of 15 μm or less. The density of the through holes in the resin film is 1 × 10 ³ pieces / cm ² or more and 1 × 10 ⁹ pieces / cm ² or less. The said resin film has the said through-hole extended in the direction inclined with respect to the direction perpendicular | vertical to the main surface of the said resin film. In the resin film, the through holes having different directions extending in an inclined manner are mixed.

  ADVANTAGE OF THE INVENTION According to this invention, the waterproof breathable film which made air permeability and waterproofness compatible in the higher level than before is obtained. According to the present invention, a waterproof sound-permeable membrane excellent in waterproofness and sound-transmitting characteristics can be obtained.

It is sectional drawing which shows typically an example of the waterproof breathable film of this invention. 4 is a schematic cross-sectional view for explaining an angle θ1 formed by a direction in which a through hole is inclined and extended with respect to a direction perpendicular to a main surface of a resin film 2 in the waterproof breathable membrane of the present invention. FIG. In the waterproof breathable membrane of the present invention, it is a top view showing typically an example of the relation between the through-holes in the direction in which the through-holes extend. In the waterproof breathable membrane of the present invention, it is a top view showing typically another example of the relation between the through holes in the direction in which the through holes extend. In the waterproof breathable membrane of the present invention, it is a top view showing typically another example of the relation between the through holes in the direction in which the through holes extend. It is sectional drawing which shows typically an example of the relationship between through-holes in the waterproof breathable film of this invention. It is sectional drawing which shows typically another example of the waterproof breathable film of this invention. It is a schematic diagram which shows an example of the method of manufacturing the waterproof breathable film of this invention. It is sectional drawing which shows typically another example of the waterproof breathable film of this invention. It is a perspective view which shows typically an example of the waterproof ventilation member of this invention. It is a top view which shows typically another example of the waterproof ventilation member of this invention. It is sectional drawing which shows typically an example of the waterproof ventilation structure of this invention. It is a perspective view which shows typically an example of an electronic device provided with the waterproof sound-permeable membrane of this invention. It is sectional drawing which shows typically arrangement | positioning of the waterproof sound-permeable membrane in the electronic device of FIG. 13A. It is a perspective view which shows typically an example of the case for electronic devices provided with the waterproof sound-permeable membrane of this invention. It is sectional drawing which shows typically arrangement | positioning of the waterproof sound-permeable membrane in the case for electronic devices of FIG. 14A. It is sectional drawing which shows typically the structure of the simulation housing | casing used in order to evaluate the sound-permeable characteristic of a waterproof sound-permeable membrane in an Example, and arrangement | positioning of a speaker, a waterproof sound-permeable membrane, and a microphone. It is a figure which shows the result of the FFT analysis with respect to the waterproof sound-permeable membrane produced in Example 2. It is a figure which shows the result of the FFT analysis with respect to the waterproof sound-permeable membrane produced in the comparative example 2. It is a figure which shows the result of the FFT analysis with respect to the waterproof sound-permeable membrane produced in Example 3. It is a figure which shows the result of the FFT analysis with respect to the waterproof sound-permeable membrane produced in Example 4.

  The present invention will be described below with reference to the drawings. The present invention is not limited to the embodiments described below.

[Waterproof breathable membrane]
FIG. 1 shows an example of the waterproof breathable membrane of the present invention. A waterproof breathable membrane 1 shown in FIG. 1 includes a non-porous resin film 2 and a liquid repellent layer 3 formed on the main surface of the resin film 2. The resin film 2 is formed with a plurality of through holes 21 (21a to 21g) penetrating in the thickness direction. The liquid repellent layer 3 has an opening 31 at a position corresponding to the through hole 21 (a position corresponding to the opening of the through hole 21 in the resin film 2). The resin film 2 is a non-porous resin film that has no path other than the through hole 21 through which air can be passed in the thickness direction. (Real) resin film. The through hole 21 has openings on both main surfaces of the resin film 2.

  The through hole 21 is a straight hole that extends linearly, that is, penetrates the resin film 2 linearly. At this time, the through hole 21 can be a hole whose diameter does not substantially change from one main surface of the resin film 2 to the other main surface. The through-hole 21 can be formed by, for example, irradiation of an ion beam onto a resin film that is an original film and chemical etching on the film after irradiation. By ion beam irradiation and etching, a large number of through holes 21 having a uniform opening diameter can be formed in the resin film 2. In addition, in the ion beam irradiation and etching, a resin having a surface in the same state as the surface of the original film except that the opening of the through hole 21 is formed when the process of processing or processing the surface of the film is not further performed. Film 2 can be obtained. For this reason, for example, if a film having a high surface smoothness is selected as the original film, a resin film 21 having a surface with a high smoothness corresponding thereto (for example, the surface is flat except for the opening) is obtained. Is possible. The original film is a non-porous film that does not have a path that allows air to flow in the thickness direction in the region to be the waterproof breathable membrane 1. The original film is typically a nonporous resin film.

  The resin film 2 has a through hole 21 extending in a direction inclined with respect to a direction perpendicular to the main surface of the film. And as shown in FIG. 1, the through-holes 21a-21g from which the direction which inclines and extends differ are mixed in the resin film 2. As shown in FIG. In other words, the through hole 21 extends in a direction inclined with respect to a direction perpendicular to the main surface of the resin film 2 (through the resin film 2), and the extending directions of the resin film 2 are different from each other. There are combinations of through holes 21. The resin film 2 may have a combination of through holes 21 having the same extending direction. In the example shown in FIG. 1, for example, the extending directions of the through holes 21a, 21b, and 21c are different from each other, and the extending directions of the through holes 21a, 21d, and 21g are the same. Hereinafter, “combination” is also simply referred to as “set” in the present specification. The “set” is not limited to the relationship (pair) between one through hole and one through hole, and means a relationship between one or two or more through holes. Having a set of through holes having the same characteristics means that there are a plurality of through holes having the characteristics.

  The resin film 2 as shown in FIG. 1 irradiates, for example, an ion beam tilted from a direction perpendicular to the main surface of the original film, and changes the tilting direction continuously or stepwise to change the film after irradiation. It can be formed by chemical etching. Since the ion beam is a beam in which a plurality of ions fly in parallel with each other, a set of through holes 21 extending in the same direction is usually present in the resin film 2 (a plurality of through holes 21 extending in the same direction are the resin film 2). Usually exists).

Through holes 21 with different directions extending at an angle are mixed in the resin film 2, the diameter of the through holes existing in the resin film 2 is 15 μm or less, and the hole density of the through holes in the resin film 2 is 1 × 10 ³ / cm 2. A waterproof breathable membrane that achieves both air permeability and waterproofness at a higher level than before by having a liquid repellent layer 3 on the main surface of the resin film 2 while being ² or more and 1 × 10 ⁹ pieces / cm ² or less. 1

  The angle θ1 (see FIG. 2) formed by the inclined hole extending direction D1 with respect to the direction D2 perpendicular to the main surface of the resin film 2 is preferably 45 ° or less, and more preferably 30 ° or less. When the angle θ1 is within these ranges, the level of compatibility between air permeability and waterproofness in the resin film 2 becomes higher. Although the minimum of angle (theta) 1 is not specifically limited, For example, it is 10 degrees or more, and 20 degrees or more are preferable. If the angle θ1 is excessively large, the mechanical strength of the waterproof gas-permeable membrane 1 tends to be weakened.

  For example, when the resin film 2 is manufactured, the angle θ1 can be controlled by the incident angle of the ion beam with respect to the original film.

  In the resin film 2, there may be a set of through holes 21 having different angles θ1.

  In the resin film 2, when viewed from a direction perpendicular to the main surface of the film 2 (when a direction in which the through hole 21 extends is projected onto the main surface), the extending directions of the through holes 21 are parallel to each other. However, it is preferable that the resin film 2 has a set in which the extending directions are different from each other (through holes 21 having different extending directions are present in the resin film 2). In the latter case, the level of both air permeability and waterproof property as the waterproof gas-permeable membrane 1 is further increased.

  FIG. 3 shows an example in which the directions in which the through holes 21 extend are parallel to each other when viewed from a direction perpendicular to the main surface of the resin film 2. In the example shown in FIG. 3, three through holes 21 (21 h, 21 i, 21 j) can be seen, but the direction in which each through hole 21 extends when viewed from the direction perpendicular to the main surface of the resin film 2 (front of the page). D3, D4, and D5 are parallel to each other (the direction from the opening 22a of the through hole 21 in the main surface on the side to the opening 22b of the through hole 21 in the main surface on the opposite side) (θ2 described later is 0 °). However, the angles θ1 of the through holes 21h, 21i, and 21j are different from each other (the angle θ1 of the through hole 21j is the smallest and the angle θ1 of the through hole 21h is the largest), and the direction in which the through holes 21h, 21i, and 21j extend is Three-dimensionally different.

  FIG. 4 shows an example in which the through holes 21 extend in different directions when viewed from a direction perpendicular to the main surface of the resin film 2. In the example shown in FIG. 4, three through holes 21 (21k, 21l, 21m) are visible, but the directions D6, D7 in which each through hole 21 extends when viewed from a direction perpendicular to the main surface of the resin film 2. , D8 are different from each other. Here, the through holes 21k and 21l form an angle θ2 of less than 90 ° when viewed from a direction perpendicular to the main surface of the resin film 2, and extend from the main surface in different directions. On the other hand, the through holes 21k and 21m form an angle θ2 of 90 ° or more when viewed from a direction perpendicular to the main surface of the resin film 2, and extend from the main surface in different directions. Like the latter, the resin film 2 has a set of through holes 21 that form an angle θ2 of 90 ° or more and extend from the main surface in different directions when viewed from a direction perpendicular to the main surface of the film. It is preferable. In other words, the resin film 2 has a through-hole 21k extending in a certain direction D6 from the main surface and 90 ° or more with respect to the certain direction D6 when viewed from a direction perpendicular to the main surface of the film. It is preferable to have a through hole 21m extending from the main surface in a direction D8 forming the angle θ2. At this time, the level of coexistence of breathability and waterproofness as the waterproof breathable membrane 1 is further increased.

  The angle θ2 is preferably 90 ° or more and 180 ° or less, that is, may be 180 °. An example in which the angle θ2 is 180 ° is shown in FIG. In the example shown in FIG. 5, two through holes 21 (21 n and 21 o) are visible, but the through holes 21 n and 21 o are antiparallel to each other when viewed from a direction perpendicular to the main surface of the resin film 2. ) In the directions D9 and D10.

  Two or more through holes 21 may intersect each other in the resin film 2. That is, the resin film 2 may have a set of through holes 21 that intersect with each other in the film 2. At this time, the level of coexistence of breathability and waterproofness as the waterproof breathable membrane 1 is particularly high. Such an example is shown in FIG. In the example shown in FIG. 6, the through holes 21 p and 21 q intersect each other in the resin film 2.

  As shown in FIG. 7, the resin film 2 may have through-holes 23 extending in a direction perpendicular to the main surface of the film in addition to the through-holes 21.

  The resin film 2 shown in FIGS. 3 to 7 can be formed, for example, by controlling the irradiation direction of the ion beam, the irradiation timing, and the shape of the beam line cross section with respect to the original film. For example, as shown in FIG. 8, the belt-shaped original film 32 is fed out from the feed roll 33 and passed through an irradiation roll 34 having a predetermined curvature, and has a predetermined cross-sectional shape and cross-sectional area while passing through the roll 34. The ion beam 36 is irradiated by a beam line, and the irradiated original film 32 is wound on a winding roll 35. At this time, since the ions in the ion beam 36 fly one after another in parallel, the angle at which the ion film collides with the main surface of the original film 32 while the original film 32 moves on the irradiation roll 34 (incident). The angle θ1) changes. If this is chemically etched, for example, a resin film 2 as shown in FIG. 7 is formed. At this time, the direction (MD direction) which conveys an original film in FIG. 8 respond | corresponds to the left-right direction of FIG.

  The extending direction of the through holes 21 and 23 (in the waterproof breathable membrane 1) in the resin film 2 can be confirmed, for example, by observing the main surface and cross section of the film with a scanning electron microscope (SEM).

  The shape of the opening of the through holes 21 and 23 is not particularly limited. For example, it may be circular or irregular.

  The diameter (opening diameter) of the through holes 21 and 23 is 15 μm or less. If the diameters of the through holes 21 and 23 are larger than this, the waterproof property as the waterproof breathable membrane 1 is lowered, and it is difficult to achieve both the breathability and the waterproof property. Although the minimum of the diameter of the through-holes 21 and 23 is not specifically limited, For example, it is 0.01 micrometer. When the diameters of the through holes 21 and 23 are excessively small, the air permeability as the waterproof gas-permeable membrane 1 is lowered, and it is difficult to achieve both the air permeability and the water resistance.

  The diameters of the through holes 21 and 23 are the diameters of the circles when the cross-sectional shape (for example, opening shape) of the through holes 21 and 23 is regarded as a circle. Since the through hole 21 extends in a direction inclined with respect to the direction perpendicular to the main surface of the resin film 2, the opening shape thereof is typically an ellipse. However, the cross-sectional shape of the through-hole 21 in the resin film 2 (cross-sectional shape cut perpendicular to the extending direction) can be regarded as a circle like the through-hole 23, and the diameter of this circle is an opening shape. Equal to the minimum diameter of the ellipse. For this reason, about the through-hole 21, the said minimum diameter can be made into the diameter of a through-hole. The same applies to the through hole 23 if the diameter of the circle is regarded as the minimum diameter of the opening shape. The diameters of the through holes 21 and 23 do not need to be the same in all the through holes 21 and 23 existing in the resin film 2, but in an effective portion of the resin film 2 (a portion that can be used as the waterproof breathable membrane 1). It is preferable that the values agree with a level that can be regarded as substantially the same value (for example, the standard deviation is 10% or less of the average value). The diameters of the through holes 21 and 23 can be adjusted by the time for etching the original film and / or the concentration of the etching treatment liquid. The diameters of all the through holes 21 and 23 existing in the effective portion of the resin film 2 can be the same.

The waterproof breathable membrane 1 is indicated by a fragile number (hereinafter simply referred to as “fragile number”) measured in accordance with JIS L1096, and is 0.01 cm ³ / (cm ² · sec) or more and 100 cm ³ / (cm ² · It is preferable to have an air permeability equal to or less than (second) in the thickness direction. Considering that the liquid repellent layer 3 has almost no influence on the air permeability, the resin film 2 is 0.01 cm ³ / (cm ² · sec) or more and 100 cm ³ / (cm ² · sec) in terms of fragile number. It can have the following air permeability in its thickness direction: At this time, the level of coexistence of breathability and waterproofness as the waterproof breathable membrane 1 becomes higher. The air permeability is expressed in terms of fragile number, and is preferably 2.0 cm ³ / (cm ² · sec) or more and 50 cm ³ / (cm ² · sec) or less, and 11 cm ³ / (cm ² · sec) or more and 50 cm ³ / (cm ² · sec) or less is more preferable.

  The porosity of the resin film 2 is preferably 50% or less, preferably 25% or more and 45% or less, and more preferably 30% or more and 40% or less. At this time, the level of coexistence of breathability and waterproofness as the waterproof breathable membrane 1 becomes higher. Further, a stretched porous membrane having a dispersed structure of innumerable pores generated by stretching cannot be a waterproof breathable membrane having such a low porosity. In addition, since the resin film 2 is a non-porous film in which a plurality of through-holes penetrating in the thickness direction are formed, the porosity is open on the main surface with respect to the area of the main surface of the resin film 2. This is the total ratio of the opening areas of the through holes 21 and 23.

The density (hole density) of the through holes 21 and 23 in the resin film 2 is 1 × 10 ³ holes / cm ² or more and 1 × 10 ⁹ holes / cm ² or less. When the pore density is less than this range, the air permeability of the waterproof gas-permeable membrane 1 is lowered. If the pore density exceeds this range, the waterproof property of the waterproof breathable membrane 1 is lowered. Pore density, 1 × 10 ⁵ / cm ² or more 5 × 10 ⁸ / cm ² or less being more preferred. The pore density does not need to be constant throughout the resin film 2, but in the effective portion of the resin film 2, it may be constant so that the maximum pore density is not more than 1.5 times the minimum pore density. preferable. The pore density can be adjusted by the ion irradiation amount when the original film is irradiated with the ion beam.

  The thickness of the resin film 2 is, for example, 10 μm or more and 100 μm or less, and preferably 15 μm or more and 50 μm or less.

  The material which comprises the resin film 2 is not limited as long as it is a material which can form the through-hole 21 in the original film which is a non-porous resin film. The resin film 2 is made of, for example, an alkaline solution, an acidic solution, or a resin that decomposes with an alkaline solution or an acidic solution to which at least one selected from an oxidizing agent, an organic solvent, and a surfactant is added. In this case, formation of the through hole 21 in the original film by ion beam irradiation and etching becomes easier. Viewed from another aspect, the resin film 2 is made of, for example, a resin that can be etched by hydrolysis or oxidative decomposition. The resin film 2 can be made of a resin that can be etched with an alkaline solution or an oxidant solution.

  The resin film 2 is composed of at least one resin selected from, for example, polyethylene terephthalate (PET), polycarbonate, polyimide, polyethylene naphthalate, and polyvinylidene fluoride.

  In the etching for forming the through holes 21 and 23, an etching treatment liquid corresponding to the material constituting the resin film 2 is selected. The etching treatment liquid is, for example, an alkaline solution, an acidic solution, or an alkaline solution or an acidic solution to which at least one selected from an oxidizing agent, an organic solvent, and a surfactant is added. The etching treatment liquid may be an alkaline solution and an oxidant solution. The alkaline solution is, for example, a solution containing potassium hydroxide and / or sodium hydroxide as a main component, and may further contain an oxidizing agent. By using an alkaline solution, the resin constituting the original film can be hydrolyzed. The oxidant solution is, for example, a solution containing at least one selected from chlorous acid, chlorite, hypochlorous acid, hypochlorite, hydrogen peroxide, and potassium permanganate as a main component. By using the oxidant solution, the resin constituting the original film can be oxidatively decomposed. An example of a combination of the resin film 2 and the resin constituting the original film and the etching treatment liquid is an alkaline solution (for example, a solution containing sodium hydroxide as a main component) for PET, polycarbonate, and polyethylene naphthalate. It is an oxidizing agent solution (for example, a solution containing sodium hypochlorite as a main component) for vinylidene chloride.

  A commercially available film can be used as the resin film 2 having the through holes 21. Commercially available films are sold as membrane filters, for example, by Oxyphen and Millipore.

  The waterproof breathable membrane 1 may have two or more resin films 2. Such a waterproof gas-permeable membrane 1 can be formed by, for example, ion beam irradiation and etching on a laminate having two or more original films.

  The liquid repellent layer 3 is a layer having water repellency, and preferably also has oil repellency. The liquid repellent layer 3 has an opening 31 at a position corresponding to the through hole 21 of the resin film 2. When the resin film 2 further has the through hole 23, the opening 31 can also be provided at a position corresponding to the through hole 23.

  The liquid repellent layer 3 is formed on the main surface of the resin film 2. The liquid repellent layer 3 only needs to be formed on at least one main surface of the resin film 2.

  Such a liquid repellent layer 3 can be formed, for example, by thinly applying a treatment liquid prepared by diluting a water repellent or a hydrophobic oil repellent with a diluent and drying it on the resin film 2. The water repellent and the hydrophobic oil repellent are, for example, perfluoroalkyl acrylate and perfluoroalkyl methacrylate. The thickness of the liquid repellent layer 3 is preferably less than ½ of the diameter of the through hole 21 (and 23).

  When the liquid repellent layer 3 is formed by thinly applying the treatment liquid onto the resin film 2, the inner peripheral surface of the through hole is also continuous with the liquid repellent layer 3 depending on the diameter of the through hole 21 (and 23). It is possible to coat with a liquid repellent layer (this is the case in the example shown in FIG. 1). In this case, the diameter of the through hole 21 (and 23) is smaller than the original diameter depending on the thickness of the liquid repellent layer.

  The waterproof gas-permeable membrane 1 may include any member other than the resin film 2 and the liquid repellent layer 3 as long as the effects of the present invention are obtained. The member is, for example, a breathable support layer 4 shown in FIG. In the waterproof gas-permeable membrane 1 shown in FIG. 9, the air-permeable support layer 4 is disposed on one main surface of the resin film 2 of the waterproof gas-permeable membrane 1 shown in FIG. By the arrangement of the air-permeable support layer 4, the strength as the waterproof gas-permeable membrane 1 is improved and the handleability is also improved.

  The breathable support layer 4 is a layer having a higher air permeability in the thickness direction than the resin film 2. For the breathable support layer 4, for example, a woven fabric, a nonwoven fabric, a net, or a mesh can be used. The material constituting the air-permeable support layer 4 is, for example, polyester, polyethylene, or aramid resin. The liquid repellent layer 3 may or may not be formed on the main surface of the resin film 2 on which the air-permeable support layer 4 is disposed. The shape of the air-permeable support layer 4 may be the same as or different from the shape of the resin film 2. For example, the breathable support layer 4 has a shape that is arranged only at the peripheral edge of the resin film 2 (specifically, when the resin film is circular, it is a ring-shaped support layer 4 that is arranged only at the peripheral edge). sell. The air-permeable support layer 4 is disposed, for example, by a technique such as thermal welding with the resin film 2 or adhesion with an adhesive.

  The breathable support layer 4 may be disposed on one main surface of the resin film 2 or may be disposed on both main surfaces.

  The waterproof gas-permeable membrane 1 preferably has a water pressure resistance of 2 kPa or more measured according to the provisions of the water resistance test method B (high water pressure method) of JIS L1092. The water pressure resistance of 2 kPa means drip-proof and rain-proof in daily life. The water pressure resistance can be 5 kPa or more, or 10 kPa or more. The water pressure resistance of 10 kPa means that it can withstand the water pressure at a depth of 1 m. In this case, waterproofness corresponding to “water protection class 7 (IPX7)” defined in JIS C0920 is secured. For example, even if a device equivalent to IPX7 is accidentally dropped into water, it can be prevented from entering the device within a predetermined depth and time. It has been empirically known that when the water pressure resistance is about 5 kPa, waterproofness corresponding to “water protection class 4 (IPX4)” defined in JIS C0920 is secured. IPX4 is also one of the waterproof properties required for electronic devices in recent years. When the waterproof pressure of the waterproof gas-permeable membrane 1 is 5 kPa or more or 10 kPa or more, both waterproof properties equivalent to IPX4 or IPX7 and air permeability can be achieved. For example, there are few restrictions on the opening space required for the waterproof air-permeable structure. Thus, a device with a high degree of design freedom including design is realized, such as miniaturization and / or thinning.

The surface density of the waterproof gas-permeable membrane 1 is preferably 5 to 100 g / m ^{2 and} more preferably 10 to 50 g / m ² from the viewpoint of the strength and handleability of the membrane.

  The thickness of the waterproof gas-permeable membrane 1 is, for example, 10 to 100 μm, and preferably 15 to 50 μm.

  The waterproof breathable membrane 1 may be subjected to a coloring treatment. Depending on the type of material constituting the resin film 2, the color of the waterproof gas-permeable membrane 1 that has not been colored is, for example, transparent or white. When such a waterproof gas-permeable membrane 1 is arranged so as to close the opening of the housing, the membrane 1 may stand out. The conspicuous membrane stimulates the user's curiosity, and the function as a waterproof breathable membrane may be impaired by piercing with a needle or the like. When the waterproof gas-permeable membrane 1 is colored, for example, by using the membrane 1 having the same color or a color similar to the color of the housing, the user's attention can be relatively suppressed. In addition, a colored waterproof breathable membrane may be required due to the design of the housing, and such a design requirement can be met by the coloring process.

  The coloring process can be performed by, for example, dyeing the resin film 2 or adding a colorant to the resin film 2. For example, the coloring treatment may be performed so that light included in a wavelength range of 380 nm to 500 nm is absorbed. That is, the waterproof gas-permeable membrane 1 may be subjected to a coloring treatment that absorbs light included in a wavelength range of 380 nm to 500 nm. For that purpose, for example, the resin film 2 includes a colorant having an ability to absorb light included in a wavelength range of 380 nm to 500 nm, or absorbs light included in a wavelength range of 380 nm to 500 nm. It is dyed by a dye having ability. In this case, the waterproof gas-permeable membrane 1 can be colored blue, gray, brown, pink, green, yellow, or the like. The waterproof air-permeable membrane 1 may be colored in black, gray, brown or pink.

  The waterproof gas-permeable membrane of the present invention can be used for the same applications as conventional waterproof gas-permeable membranes.

[Waterproof sound-permeable membrane]
The waterproof breathable membrane 1 of the present invention accommodates an acoustic part such as a microphone, a speaker, and a transducer, and a casing provided with an opening for transmitting sound between the acoustic part and the outside, and closes the opening. Thus, it can be used as a waterproof sound-permeable membrane that transmits sound between the acoustic part and the outside and prevents water from entering the casing through the opening from the outside. At this time, the waterproof sound-permeable membrane (waterproof sound-permeable membrane of the present invention) includes a non-porous resin film 2 in which a plurality of through-holes 21 penetrating in the thickness direction are formed, and a main part of the resin film 2. And a liquid repellent layer 3 having openings 31 at positions corresponding to the plurality of through holes 21, the through holes 21 extending linearly and having a diameter (opening diameter) of 15 μm or less. The hole density of the through holes 21 in the resin film 2 is 1 × 10 ³ pieces / cm ² or more and 1 × 10 ⁹ pieces / cm ² or less, and the resin film 2 is the main film 2 of the film 2. The waterproof sound-permeable membrane includes the through-holes 21 extending in a direction inclined with respect to a direction perpendicular to the surface, and the through-holes 21 having different directions extending in an inclined manner are mixed in the resin film 2.

Through holes 21 having different directions extending at an inclination are mixed in the resin film 2, the diameter of the through holes existing in the resin film 2 is 15 μm or less, and the hole density of the through holes in the resin film 2 is 1 ×.
10 ³ pieces / cm ² or more and 1 × 10 ⁹ pieces / cm ² or less, and by having the liquid repellent layer 3 on the main surface of the resin film 2, Become. In addition, the said effect as a waterproof sound-permeable membrane does not necessarily originate in the effect as a waterproof breathable membrane, ie, the coexistence (balance) in the level higher than the conventional air permeability and waterproofness. The effect as a waterproof sound-permeable membrane is derived from the structure of the film, particularly the structure of the resin film 2. In other words, the film including the resin film 2 and the liquid repellent layer 3 having the above-described structure can be used as a waterproof gas permeable film or a waterproof sound permeable film, and each achieves the predetermined effect described above. That is.

  The resin film 2 and the liquid repellent layer 3 included in the waterproof sound-permeable membrane of the present invention can have the same configuration as the resin film 2 and the liquid repellent layer 3 included in the waterproof air-permeable membrane 1 described above. Its main effect is the realization of higher waterproofness and sound transmission characteristics. However, considering the fact that it is a sound-permeable membrane, it is more preferable to satisfy the following characteristics.

  The upper limit of the diameter (opening diameter) of the through holes 21 and 23 is preferably 12 μm or less. The diameters of the through holes 21 and 23 are preferably 4.5 μm or more and 12 μm or less, and more preferably 5 μm or more and 11 μm or less. In this range, the sound transmission characteristics are further improved.

The waterproof sound-permeable membrane is indicated by the above-mentioned fragile number, preferably 5.0 cm ³ / (cm ² · sec) or more and 50 cm ³ / (cm ² · sec) or less, more preferably 11 cm ³ / (cm ² · sec). It is preferable to have an air permeability in the thickness direction of 50 cm ³ / (cm ² · sec) or less. In this range, the sound transmission characteristics are further improved.

  The waterproof sound-permeable membrane of the present invention has high sound-permeable characteristics. High sound transmission characteristics are, for example, reduced “chattering noise”. If the chatter sound is generated more strongly, for example, the sound quality of the sound and music emitted from the speaker, and the sound quality of the sound and music received by the microphone will deteriorate, and the performance, function and appeal of the product as a product will decrease. . According to the waterproof sound-permeable membrane of the present invention, for example, generation of chatter noise due to the placement of the waterproof sound-permeable membrane is suppressed while providing high waterproofness to the opening for transmitting sound to / from the acoustic unit, and The performance, function, and appeal of the product as an electronic device equipped with a sound membrane can be improved.

  As a result of the study by the present inventors, it has been found that the chatter sound of the sound-permeable membrane can be evaluated as follows. When the sound passes through the waterproof sound-permeable membrane, the chatter sound is generated by inducing a sound having a frequency higher than the frequency of the sound, more specifically, a sound having a frequency range of 5 kHz to 20 kHz. If the generation of the induced sound in such a high sound range is suppressed, the generation of chatter noise due to the arrangement of the waterproof sound-permeable membrane is suppressed.

The waterproof sound-permeable membrane of the present invention has, for example, an input sound having a waveform of a sine wave and maintaining the sound pressure level so that the sound pressure level of the sound having a frequency of 1 kHz after passing through the membrane is 94 dB, Starting from 100 Hz, when the frequency is continuously increased at a rate of 100 Hz / second and input to the membrane having an effective area of 132.7 mm ² , the input sound is input until 20 seconds elapse from the start of input. The ratio A between the integrated sound pressure level A in the sound range of frequency 100 Hz to 20 kHz and the integrated sound pressure level B in the sound frequency range of 5 kHz to 20 kHz, obtained by FFT (Fast Fourier Transform) analysis for the sound that has passed through the membrane. A waterproof sound-permeable membrane with / B of 1.16 or more. In such a waterproof sound-permeable membrane, generation of induced sound in the high sound range is suppressed, and chatter noise is less generated.

The sound pressure level of the input sound is adjusted at a frequency of 1 kHz because the sound having a frequency of 1 kHz corresponds to a standard human voice and can be heard most sharply in the audible range. Based on something. In the above measurement, the input sound whose sound pressure level has been adjusted in this way is input to the waterproof sound-permeable membrane while continuously changing the frequency, and is transmitted through the membrane, and FFT analysis is performed on the transmitted sound. The membrane having an effective area of 132.7 mm ² is assumed to be a waterproof sound-permeable membrane having a circular effective portion having a radius of 6.5 mm. The effective area is the part where sound is actually input to the membrane when the waterproof sound-permeable membrane is placed so as to block the opening of the housing, and the sound is output from the membrane through the membrane (effective For example, it does not include the area of the support or adhesive portion that is disposed and formed on the peripheral edge of the membrane in order to dispose the waterproof sound-permeable membrane. The effective area is typically the area of the opening in which the membrane is arranged or the area of the opening in the waterproof sound-permeable member in which the support is arranged at the periphery of the waterproof sound-permeable membrane. It is possible.

  The integrated sound pressure level is a value obtained by integrating the sound pressure levels of sounds within the specific frequency range in the frequency direction, and is a general acoustic analysis (evaluation) apparatus or acoustic analysis that performs FFT analysis of the sound. (Evaluation) Can be obtained by software.

  The ratio A / B is preferably 1.16 or more, more preferably 1.25 or more. As the ratio A / B is larger, the waterproof sound-permeable membrane is suppressed from generating chatter noise.

The waterproof sound-permeable membrane of the present invention further has an input sound having a waveform of a sine wave and maintaining the sound pressure level so that the sound pressure level of the sound having a frequency of 1 kHz after passing through the membrane is 94 dB, Starting from 100 Hz, when the frequency is continuously increased at a rate of 100 Hz / second and input to the membrane having an effective area of 132.7 mm ² , the input sound is input until 20 seconds elapse. The sound transmitted through the membrane may be a waterproof sound-permeable membrane in which a sound pressure level of 40 dB or more is observed in a sound region of a frequency of 5 kHz or more and 20 kHz or less, and the frequency range of the input sound is 1.3 kHz or less. With such a film, the occurrence of chatter noise is further reduced. When the frequency of the input sound is increased from 100 Hz, at a certain frequency (minimum frequency F _min ), the transmitted sound includes a component belonging to the sound range of the frequency of 5 kHz or more and 20 kHz or less and having a sound pressure level of 40 dB or more. Will occur. When the frequency of the input sound is further increased, the above components are not included in the transmitted sound at another frequency (maximum frequency F _max ). When the difference ΔF between F _max and F _min is 1.3 kHz or less, a waterproof sound-permeable membrane with less chatter noise is obtained. However, the maximum value of F _max is 2 kHz 20 seconds after the start of input. ΔF is preferably 1.3 kHz or less, and more preferably 1.1 kHz or less. When the transmitted sound including the above components is intermittently generated when the frequency of the input wave is increased from 100 Hz, the input frequency at which the above components are finally not included in the transmitted sound is F _max (however, the maximum value) Is 2 kHz 20 seconds after the start of input).

The waterproof sound-permeable membrane of the present invention further has an input sound having a waveform of a sine wave and maintaining the sound pressure level so that the sound pressure level of the sound having a frequency of 1 kHz after passing through the membrane is 94 dB, Starting from 100 Hz, when the frequency is continuously increased at a rate of 100 Hz / second and input to the membrane having an effective area of 132.7 mm ² , the input sound is input until 20 seconds elapse. The sound transmitted through the membrane may be a waterproof sound-permeable membrane in which a sound pressure level of 40 dB or more is observed in a sound range of a frequency of 5 kHz to 20 kHz, and a maximum frequency F _max of the input sound is 1.5 kHz or less. Such a waterproof sound-permeable membrane particularly reduces the occurrence of chatter noise. The F _max is preferably 1.5 kHz or less, more preferably 1.1 kHz or less.

[Waterproof ventilation member and waterproof sound transmission member]
An example of the waterproof ventilation member of the present invention is shown in FIG. The waterproof ventilation member 5 shown in FIG. 10 is a waterproof ventilation membrane 1 having a circular shape when viewed from a direction perpendicular to the main surface of the membrane, and a support body that is a ring-shaped sheet joined to the peripheral edge of the membrane 1. 51. The form in which the support body 51 is joined to the waterproof gas-permeable membrane 1 reinforces the waterproof gas-permeable membrane 1 and improves its handleability. Moreover, since the support body 51 becomes an allowance to the part to which the waterproof ventilation member 5 is arrange | positioned, such as opening of a housing | casing, the attachment operation | work of the waterproof ventilation film 1 becomes easy.

  The shape of the support body 51 is not limited. For example, as shown in FIG. 11, even if it is the support body 51 which is a frame-shaped sheet | seat joined to the peripheral part of the waterproof breathable film 1 whose shape seen from the direction perpendicular | vertical to the main surface of a film | membrane is a rectangle. Good. As shown in FIGS. 10 and 11, by reducing the shape of the support 51 to the shape of the periphery of the waterproof gas-permeable membrane 1, a decrease in the air permeability of the waterproof gas-permeable membrane 1 due to the arrangement of the support 51 is suppressed. Moreover, the sheet-like support body 51 is preferable from the viewpoints of the handleability of the waterproof ventilation member 5 and the disposition property to the housing, particularly the disposition property within the housing. In the example shown in FIGS. 10 and 11, the waterproof gas-permeable membrane 1 is exposed except for the peripheral portion where the support body 51 is disposed (both surfaces of the waterproof gas-permeable membrane 1 are exposed).

  The material which comprises the support body 51 is resin, a metal, and these composite materials, for example. The resin is, for example, a polyolefin such as polyethylene or polypropylene; a polyester such as PET or polycarbonate; a polyimide or a composite material thereof. The metal is a metal having excellent corrosion resistance, such as stainless steel or aluminum.

  The thickness of the support 51 is, for example, 5 to 500 μm, and preferably 25 to 200 μm. When attention is paid to the function as an attachment margin, the ring width (frame width: difference between the outer shape and the inner diameter) is suitably about 0.5 to 2 mm. For the support 51, a foam made of the above resin may be used.

  The joining method of the waterproof gas-permeable membrane 1 and the support 51 is not particularly limited, and for example, methods such as heat welding, ultrasonic welding, adhesion using an adhesive, and adhesion using a double-sided tape can be employed.

  The waterproof ventilation member 5 may include two or more waterproof ventilation membranes 1 and / or two or more supports 51.

  The waterproof ventilation member of the present invention can be used for the same application as that of a conventional waterproof ventilation member. Moreover, the waterproof ventilation member of this invention can be used as a waterproof sound-permeable member by using the waterproof ventilation film with which the said member is provided as a waterproof sound-permeable membrane. At this time, the waterproof sound-permeable member includes the waterproof breathable membrane (sound-permeable membrane) of the present invention and a support joined to the waterproof breathable membrane (sound-permeable membrane). The configuration of the support can be the same as the configuration of the support 51 of the waterproof ventilation member.

[Waterproof ventilation structure and waterproof sound transmission structure]
An example of the waterproof ventilation structure of the present invention is shown in FIG. The waterproof ventilation structure 8 shown in FIG. 12 includes a casing 81 provided with an opening 82 for allowing gas to pass between the inside 83 and the outside, and a waterproof ventilation film 1 arranged so as to close the opening (opening) 82. With. The opening 82 is a space that connects the inside and the outside of the housing 81, and gas can travel between the inside and the outside of the housing 81 through the opening. The waterproof breathable membrane 1 can prevent water from entering the housing 81 from the outside through the opening 82 while allowing gas to pass between the outside and the inside 83 of the housing 81. In the example shown in FIG. 12, the waterproof gas-permeable membrane 1 is bonded to the housing 81 via the support body 51. In other words, a waterproof ventilation member including the waterproof ventilation membrane 1 and the support 51 is joined to the housing 81. In the example shown in FIG. 12, the waterproof gas-permeable membrane 1 is joined to the housing 81 from the inside 83 of the housing 81, but may be joined from the outside of the housing 81.

  The casing 81 is made of resin, metal, glass, and a composite material thereof.

  For the arrangement of the waterproof gas-permeable membrane 1, techniques such as sticking using double-sided tape, thermal welding, high-frequency welding, and ultrasonic welding can be employed. The support 51 may be a double-sided tape.

  Parts, devices, devices, products, etc. having the waterproof ventilation structure 8 are not limited.

  The waterproof ventilation structure of the present invention can be applied to various uses as in the conventional waterproof ventilation structure. Moreover, the waterproof ventilation structure of this invention can be used as a waterproof sound-permeable structure by using the waterproof ventilation film with which the said structure is provided as a waterproof sound-permeable film. At this time, this waterproof sound transmission structure transmits sound between a housing provided with an opening for transmitting sound between the inside and the outside, and the inside and the outside arranged so as to close the opening. And a waterproof sound-permeable membrane that prevents water from entering the inside through the opening, and the waterproof sound-permeable membrane is the waterproof breathable membrane (sound-permeable membrane) of the present invention. The structure of the housing and the bonding of the waterproof sound-permeable membrane to the housing can be the same as the waterproof ventilation structure.

  An example of applying the waterproof ventilation structure of the present invention as a waterproof sound transmission structure is an electronic device. More specifically, the electronic device includes a housing in which an acoustic unit is accommodated and an opening for transmitting sound between the acoustic unit and the outside, and the acoustic unit disposed so as to close the opening. A waterproof sound-permeable membrane that transmits sound between the portion and the outside and prevents water from entering the housing from the outside through the opening, and the waterproof sound-permeable membrane is waterproof according to the present invention. It is a gas permeable membrane (sound permeable membrane).

  An example of the electronic device is illustrated in FIG. 13A. The electronic device illustrated in FIG. 13A is a smartphone that is a type of mobile phone. The housing 61 of the smartphone 6 includes an opening 62a provided in the vicinity of a transducer that is a kind of sound generation part and sound receiving part, and an opening 62b provided in the vicinity of a microphone that is a kind of sound receiving part, And an opening 62c provided in the vicinity of a speaker which is a kind of sound generation unit. Sound is transmitted between the outside of the smartphone 6 and each acoustic unit (transducer, microphone, and speaker) accommodated in the housing 61 via the openings 62a to 62c. As shown in FIG. 13B, in the smartphone 6, a waterproof gas-permeable membrane (sound-permeable membrane) 1 is attached to the housing 61 from the inside so as to close these openings 62 a to 62 c. Thereby, while being able to transmit a sound between the exterior of the smart phone 6, and an acoustic part, it can prevent that water permeates into the housing | casing 61 via an opening from the exterior.

  The location and method of disposing the waterproof gas-permeable membrane (sound-permeable membrane) 1 in the electronic device 6 are not limited as long as the opening (opening) provided in the housing 61 of the device 6 is closed by the membrane. In the example shown in FIG. 13B, the waterproof gas-permeable membrane (sound-permeable membrane) 1 is joined to the housing 61 via the support 51 (that is, as a waterproof gas-permeable member (sound-permeable member)). For the arrangement of the waterproof gas-permeable membrane (sound-permeable membrane) 1 in the electronic device 6, a technique such as sticking using a double-sided tape, thermal welding, high-frequency welding, or ultrasonic welding can be employed. The support 51 may be a double-sided tape.

  The casing 61 is made of resin, metal, glass, and a composite material thereof. The display unit of the electronic device 6 may constitute a part of the housing 61 like a smartphone and a tablet computer.

  The electronic device is not limited to the smartphone 6. The housing is provided with an opening for transmitting sound between the outside and the sound section, and it is necessary to prevent water from entering through the opening. This applies to all types of electronic devices in which the film 1 can be disposed so as to close the opening. The electronic device is, for example, a mobile phone such as a feature phone and a smartphone, a tablet computer, a wearable computer, a PDA, a game device, a mobile computer such as a notebook computer, an electronic notebook, a digital camera, a video camera, and an electronic book reader.

  Of course, an electronic device having a waterproof ventilation structure may be used for the purpose of simply ensuring ventilation and waterproofing without considering sound transmission. This electronic device is arranged so as to block the opening and a housing having an opening, and allows water to enter the inside through the opening while allowing gas to pass between the inside and the outside of the housing. With waterproof breathable membrane to prevent. This waterproof gas-permeable membrane is the waterproof gas-permeable membrane of the present invention.

  Another example in which the waterproof ventilation structure of the present invention is applied as a waterproof sound transmission structure is an electronic device case. More specifically, this electronic device case is an electronic device case that houses an electronic device having an acoustic part, and is provided with an opening for transmitting sound between the acoustic part of the electronic device and the outside, A waterproof sound-permeable membrane disposed so as to close the opening and transmitting sound between the acoustic part of the electronic device and the outside and preventing water from entering the case from the outside through the opening The waterproof sound-permeable membrane is the waterproof breathable membrane (sound-permeable membrane) of the present invention.

  An example of an electronic device case is shown in FIG. 14A. The case 7 shown in FIG. 14A is provided with openings 71 a to 71 c that transmit sound between the acoustic unit of the electronic device housed in the case 7 and the outside of the case 7. The case 7 shown in FIG. 14A is a case of a smartphone different from the smartphone 6 shown in FIG. 13A, and the opening 71a transmits sound from the receiving part of the smartphone. In order to transmit the sound, the openings 71c are provided to transmit the sound from the speaker of the smartphone to the outside. As shown in FIG. 14B, the case 7 further includes a waterproof gas-permeable membrane (sound-permeable membrane) 1 disposed so as to close the openings 71a (71b, 71c). Sound is transmitted between the sound part of the electronic device housed in the inside 72 of the case 7 and the outside by the film, and the inside 72 of the case 7 through the openings 71a (71b, 71c), and thus the outside. Water can be prevented from entering the electronic equipment.

  The method of disposing the waterproof gas-permeable membrane (sound-permeable membrane) 1 in the electronic device case 7 is not limited as long as the openings (openings) 71a (71b, 71c) are closed by the membrane 1. In the example shown in FIG. 14B, the waterproof gas-permeable membrane (sound-permeable membrane) 1 is joined from the inside 72 to the case 7 via the support body 51 (that is, as a waterproof gas-permeable member (sound-permeable member)). For the arrangement of the waterproof gas-permeable membrane (sound-permeable membrane) 1 on the case 7, techniques such as sticking using double-sided tape, thermal welding, high-frequency welding, ultrasonic welding, etc. can be employed. The support 51 may be a double-sided tape. It is also possible to dispose a waterproof gas-permeable membrane (sound-permeable membrane) 1 from the outside of the case 7.

  The electronic device case 7 is made of resin, metal, glass, and a composite material thereof. The electronic device case 7 can have any configuration as long as the effects of the present invention can be obtained. For example, the case 7 shown in FIG. 14A is a case for a smartphone, and includes a film 73 that can operate a touch panel of a smartphone accommodated therein from the outside.

  Of course, it is good also as a case for electronic devices which has a waterproof ventilation structure for the purpose of ensuring air permeability and waterproofness without considering sound permeability. This case for an electronic device has an opening, is arranged so as to close the opening, and allows water to enter inside through the opening while allowing gas to pass between the inside and outside of the case. With waterproof breathable membrane to prevent. This waterproof gas-permeable membrane is the waterproof gas-permeable membrane of the present invention.

  Hereinafter, the present invention will be described more specifically with reference to examples. The present invention is not limited to the following examples.

  Initially, the evaluation method of the resin film and waterproof breathable film which were produced in the Example and the comparative example is demonstrated.

[Diameter of through hole]
Both main surfaces of the resin film are observed with a scanning electron microscope (SEM), and the minimum diameters of 10 through holes arbitrarily selected from the obtained SEM images are obtained from the respective images, and the average value thereof is calculated. The diameter of the through hole was used.

[Air permeability]
The air permeability in the thickness direction of the waterproof air-permeable membrane was determined in accordance with the provisions of JIS L1096 (Breathability measurement method A: Frazier method).

[Water pressure resistance]
The water pressure resistance of the waterproof breathable membrane was determined in accordance with the provisions of the water resistance test method B (high water pressure method) of JIS L1092. However, since the membrane is significantly deformed in the area of the test piece indicated in this regulation, a stainless steel mesh (opening diameter 2 mm) is placed on the opposite side of the pressure surface of the membrane, and measurement is performed with the membrane deformed to some extent. did.

[Pore density]
The hole density of the resin film was determined by observing both main surfaces of the resin film with SEM, counting the number of through holes in the obtained SEM image, and dividing this by the unit area.

[Oil repellency]
The oil repellency of the waterproof breathable membrane was evaluated as follows. Place the waterproof breathable membrane and copy paper (plain paper) on top of each other so that the waterproof breathable membrane is on top and the copy paper is on the bottom, drop a drop of castor oil on the waterproof breathable membrane with a dropper, and leave for 1 minute did. Thereafter, the waterproof breathable film was removed, and the state of the copy paper was confirmed. When the copy paper was wet with castor oil, the waterproof breathable film was not oil-repellent, and when it was not wet, the oil-repellent was given.

Example 1
A non-porous commercially available PET film (it4ip, Track etched membrane, thickness 44 μm) in which a plurality of through holes penetrating in the thickness direction was formed was prepared. This film is a film produced by irradiating a non-porous PET film with an ion beam and chemically etching the irradiated film. When the surface and cross section of this film were observed by SEM, (1) the through hole was a straight hole having a diameter of 6.5 μm, and (2) the through hole extending in a direction inclined with respect to the main surface of the film. And through-holes extending in a direction perpendicular to the main surface are mixed in the film, and (3) all through-holes extending in a direction inclined with respect to the main surface of the film are in the extending direction. Is in a direction forming an angle θ1 of 30 ° or less with respect to a direction perpendicular to the main surface, and (4) one direction as viewed from a direction perpendicular to the main surface of the film as a through hole extending in a tilted direction And a group extending in the direction opposite to the direction (a group having an angle θ2 of 180 °) are mixed, and (5) there are a plurality of sets of through holes intersecting in the film. confirmed. The hole density of the film was 1.8 × 10 ⁶ holes / cm ² .

  Next, after applying a liquid repellent treatment liquid to the entire surface including the front and back surfaces of this film, the film was allowed to stand at room temperature for 30 minutes and dried to form a liquid repellent layer on the surface of the film to obtain a waterproof breathable film. . The liquid repellent treatment liquid was prepared by diluting a liquid repellent (X-70-029C, manufactured by Shin-Etsu Chemical Co., Ltd.) with a diluent (manufactured by Shin-Etsu Chemical Co., Ltd., FS thinner) so as to have a concentration of 0.7% by weight.

The waterproof breathable membrane thus obtained had an air permeability (fragile) of 18.5 cm ³ / (cm ² · sec), a water pressure resistance of 15 kPa, and an oil repellency of “Yes”.

(Comparative Example 1)
A non-porous commercially available PET film (it4ip, Track etched membrane, thickness 44 μm) in which a plurality of through holes penetrating in the thickness direction was formed was prepared. This film is a film produced by irradiating a non-porous PET film with an ion beam and chemically etching the irradiated film. When the surface and cross section of this film were observed by SEM, (1) the through hole was a straight hole having a diameter of 6.5 μm, and (2) the through hole extending in a direction perpendicular to the main surface of the film. It was confirmed that only was present in the film. The hole density of the film was 1.8 × 10 ⁶ holes / cm ² , the same as in the example.

  Next, after applying a liquid repellent treatment liquid to the entire surface including the front and back surfaces of this film, the film was allowed to stand at room temperature for 30 minutes and dried to form a liquid repellent layer on the surface of the film to obtain a waterproof breathable film. . The liquid repellent treatment liquid was prepared by diluting a liquid repellent (X-70-029C, manufactured by Shin-Etsu Chemical Co., Ltd.) with a diluent (manufactured by Shin-Etsu Chemical Co., Ltd., FS thinner) so as to have a concentration of 0.7% by weight.

The waterproof breathable membrane thus obtained had an air permeability (fragile) of 17.1 cm ³ / (cm ² · sec), a water pressure resistance of 9 kPa, and an oil repellency of “Yes”.

  In Example 1, both the air permeability and the water pressure resistance of the waterproof gas-permeable membrane were improved as compared with Comparative Example 1.

(Example 2)
A non-porous commercially available PET film (it4ip, Track etched membrane, thickness 44 μm) in which a plurality of through holes penetrating in the thickness direction was formed was prepared. This film is a film produced by irradiating a non-porous PET film with an ion beam and chemically etching the irradiated film. When the surface and cross section of this film were observed by SEM, (1) the through hole was a straight hole having a diameter of 5.5 μm, and (2) the through hole extending in a direction inclined with respect to the main surface of the film. And through-holes extending in a direction perpendicular to the main surface are mixed in the film, and (3) all through-holes extending in a direction inclined with respect to the main surface of the film are in the extending direction. Is in a direction forming an angle θ1 of 30 ° or less with respect to a direction perpendicular to the main surface, and (4) one direction as viewed from a direction perpendicular to the main surface of the film as a through hole extending in a tilted direction And a group extending in the direction opposite to the direction (a group having an angle θ2 of 180 °) are mixed, and (5) there are a plurality of sets of through holes intersecting in the film. confirmed. The hole density of the film was 1.8 × 10 ⁶ holes / cm ² .

  Next, after applying a liquid repellent treatment liquid to the entire surface including the front and back surfaces of this film, the film was allowed to stand at room temperature for 30 minutes and dried to form a liquid repellent layer on the surface of the film to obtain a waterproof breathable film. . The liquid repellent treatment liquid was prepared by diluting a liquid repellent (X-70-029C, manufactured by Shin-Etsu Chemical Co., Ltd.) with a diluent (manufactured by Shin-Etsu Chemical Co., Ltd., FS thinner) so as to have a concentration of 0.7% by weight.

The waterproof breathable membrane thus obtained had an air permeability (Fragile) of 8.0 cm ³ / (cm ² · sec), a water pressure resistance of 18 kPa, and an oil repellency of “Yes”.

(Comparative Example 2)
A non-porous commercially available PET film (it4ip, Track etched membrane, thickness 44 μm) in which a plurality of through holes penetrating in the thickness direction was formed was prepared. This film is a film produced by irradiating a non-porous PET film with an ion beam and chemically etching the irradiated film. When the surface and cross section of this film were observed by SEM, (1) the through hole was a straight hole having a diameter of 5.5 μm, and (2) the through hole extending in a direction perpendicular to the main surface of the film. It was confirmed that only was present in the film. The hole density of the film was 1.8 × 10 ⁶ holes / cm ² , the same as in the example.

  Next, after applying a liquid repellent treatment liquid to the entire surface including the front and back surfaces of this film, the film was allowed to stand at room temperature for 30 minutes and dried to form a liquid repellent layer on the surface of the film to obtain a waterproof breathable film. . The liquid repellent treatment liquid was prepared by diluting a liquid repellent (X-70-029C, manufactured by Shin-Etsu Chemical Co., Ltd.) with a diluent (manufactured by Shin-Etsu Chemical Co., Ltd., FS thinner) so as to have a concentration of 0.7% by weight.

The waterproof breathable membrane thus obtained had an air permeability (fragile) of 5.0 cm ³ / (cm ² · sec), a water pressure resistance of 11 kPa, and an oil repellency of “Yes”.

  In Example 2, both the air permeability and the water pressure resistance of the waterproof gas-permeable membrane were improved as compared with Comparative Example 2.

(Example 3)
A non-porous commercially available PET film (it4ip, Track etched membrane, thickness 44 μm) in which a plurality of through holes penetrating in the thickness direction was formed was prepared. This film is a film produced by irradiating a non-porous PET film with an ion beam and chemically etching the irradiated film. When the surface and cross section of this film were observed by SEM, (1) the through hole was a straight hole having a diameter of 5.9 μm, and (2) the through hole extending in a direction inclined with respect to the main surface of the film. And through-holes extending in a direction perpendicular to the main surface are mixed in the film, and (3) all through-holes extending in a direction inclined with respect to the main surface of the film are in the extending direction. Is in a direction forming an angle θ1 of 30 ° or less with respect to a direction perpendicular to the main surface, and (4) one direction as viewed from a direction perpendicular to the main surface of the film as a through hole extending in a tilted direction And a group extending in the direction opposite to the direction (a group having an angle θ2 of 180 °) are mixed, and (5) there are a plurality of sets of through holes intersecting in the film. confirmed. The hole density of the film was 2.0 × 10 ⁶ holes / cm ² .

  Next, after applying a liquid repellent treatment liquid to the entire surface including the front and back surfaces of this film, the film was allowed to stand at room temperature for 30 minutes and dried to form a liquid repellent layer on the surface of the film to obtain a waterproof breathable film. . The liquid repellent treatment liquid was prepared by diluting a liquid repellent (X-70-029C, manufactured by Shin-Etsu Chemical Co., Ltd.) with a diluent (manufactured by Shin-Etsu Chemical Co., Ltd., FS thinner) so as to have a concentration of 0.7% by weight.

The waterproof breathable membrane thus obtained had an air permeability (fragile) of 25.0 cm ³ / (cm ² · sec), a water pressure resistance of 17 kPa, and an oil repellency of “Yes”.

(Comparative Example 3)
A non-porous commercially available PET film (it4ip, Track etched membrane, thickness 44 μm) in which a plurality of through holes penetrating in the thickness direction was formed was prepared. This film is a film produced by irradiating a non-porous PET film with an ion beam and chemically etching the irradiated film. When the surface and cross section of this film were observed by SEM, (1) the through hole was a straight hole having a diameter of 5.9 μm, and (2) the through hole extending in a direction perpendicular to the main surface of the film. It was confirmed that only was present in the film. The hole density of the film was 2.0 × 10 ⁶ holes / cm ² , the same as in the example.

  Next, after applying a liquid repellent treatment liquid to the entire surface including the front and back surfaces of this film, the film was allowed to stand at room temperature for 30 minutes and dried to form a liquid repellent layer on the surface of the film to obtain a waterproof breathable film. . The liquid repellent treatment liquid was prepared by diluting a liquid repellent (X-70-029C, manufactured by Shin-Etsu Chemical Co., Ltd.) with a diluent (manufactured by Shin-Etsu Chemical Co., Ltd., FS thinner) so as to have a concentration of 0.7% by weight.

The waterproof breathable membrane thus obtained had an air permeability (fragile) of 14.5 cm ³ / (cm ² · sec), a water pressure resistance of 10 kPa, and an oil repellency of “Yes”.

  In Example 3, both the air permeability and the water pressure resistance of the waterproof gas-permeable membrane were improved as compared with Comparative Example 3.

Example 4
A non-porous commercially available PET film (it4ip, Track etched membrane, thickness 44 μm) in which a plurality of through holes penetrating in the thickness direction was formed was prepared. This film is a film produced by irradiating a non-porous PET film with an ion beam and chemically etching the irradiated film. When the surface and cross section of this film were observed by SEM, (1) the through hole was a straight hole having a diameter of 10.0 μm, and (2) the through hole extending in a direction inclined with respect to the main surface of the film. And through-holes extending in a direction perpendicular to the main surface are mixed in the film, and (3) all through-holes extending in a direction inclined with respect to the main surface of the film are in the extending direction. Is in a direction forming an angle θ1 of 30 ° or less with respect to a direction perpendicular to the main surface, and (4) one direction as viewed from a direction perpendicular to the main surface of the film as a through hole extending in a tilted direction And a group extending in the direction opposite to the direction (a group having an angle θ2 of 180 °) are mixed, and (5) there are a plurality of sets of through holes intersecting in the film. confirmed. The hole density of the film was 5.0 × 10 ⁵ holes / cm ² .

  Next, after applying a liquid repellent treatment liquid to the entire surface including the front and back surfaces of this film, the film was allowed to stand at room temperature for 30 minutes and dried to form a liquid repellent layer on the surface of the film to obtain a waterproof breathable film. . The liquid repellent treatment liquid was prepared by diluting a liquid repellent (X-70-029C, manufactured by Shin-Etsu Chemical Co., Ltd.) with a diluent (manufactured by Shin-Etsu Chemical Co., Ltd., FS thinner) so as to have a concentration of 0.7% by weight.

The waterproof breathable membrane thus obtained had an air permeability (fragile) of 50.0 cm ³ / (cm ² · sec), a water pressure resistance of 6 kPa, and an oil repellency of “Yes”.

  The results so far are summarized in Table 1 below.

  Next, the waterproof gas-permeable membranes of Examples 2 to 4 and Comparative Example 2 were assumed to be used as waterproof sound-permeable membranes, and the sound-permeable characteristics were evaluated as follows.

  First, as shown in FIG. 15, a simulated casing 91 (made of polystyrene, outer dimensions 60 mm × 50 mm × 28 mm) imitating the casing of a mobile phone was prepared. The simulated housing 91 is provided with a speaker mounting hole 92 (circular with a diameter of 13 mm) serving as an opening for transmitting the sound output from the speaker to the outside of the housing, and a conducting port 93 of the speaker cable 96. There is no opening other than that.

Next, double-sided tape (manufactured by Nitto Denko, No.5620A, thickness 0.2 mm) was prepared, and this was punched into a ring shape with an inner diameter of 13 mm and an outer diameter of 16 mm to produce a plurality of ring-shaped supports 51. did. Separately, the waterproof gas-permeable membrane 1 (waterproof sound-permeable membrane) produced in Examples 2 to 4 and Comparative Example 2 was punched into a circle having a diameter of 16 mm. Next, the support 51, the waterproof gas-permeable membrane 1 and the support 51 were laminated in this order with the same outer shape, and a sample for evaluating sound transmission characteristics was obtained. The effective area of the sound-permeable membrane in this sample was 132.7 mm ² (corresponding to the area of a circle having a diameter of 13 mm).

  Next, each produced sample was affixed inside the speaker mounting hole 92 of the simulated housing 91 using one of the supports (double-sided tape) 51 as shown in FIG. At this time, the effective portion of the sound-permeable membrane of the sample was made to coincide with the opening of the speaker mounting hole 92. Then, using the other support (double-sided tape) 51 of the sample, as shown in FIG. 15, a speaker 95 (Star Precision, SCG-16A, 16 mm outer shape circle) was further attached. At this time, the external shape of the sample was matched with the external shape of the speaker. The speaker cable 96 of the speaker 95 is led out of the casing 91 from the conduction port 93, and then the conduction hole 93 is closed with putty.

  Next, the speaker cable 96 and the microphone 97 (Bruel & Kjaer Sound & Vibration Measurement A / S (B & K), Type 2669) are connected to the acoustic evaluation device (B & K, Multi-analyzer System 3560-B-030). The microphone 97 is disposed at a position 50 mm away from the front surface of the speaker 95 housed in the simulated housing 91. Next, FFT analysis (test signal 100 Hz to 20 kHz, sweep) was selected and executed as the evaluation method, and the sound passing characteristics (sound pressure level, integrated sound pressure level) of each sample were evaluated. At this time, in order to compare the evaluation results of the samples, the sound pressure level of the sound output from the speaker 95 (the sound input to the sample) is 94 dB as the sound pressure level of the sound having a frequency of 1 kHz after passing through the sample. It adjusted so that it might become. The sound input to the sample was a sine wave, and the frequency was continuously increased at a rate of 100 Hz / second starting from a frequency of 100 Hz. The sound pressure level and the integrated sound pressure level of the sound transmitted through the sample and received by the microphone 97 can be automatically obtained by the sound evaluation apparatus over an arbitrary measurement time range. In the present example, the sound passing characteristics of the sample were evaluated such that the sound pressure level of the sound and the integrated sound pressure level were obtained over a range from the start of measurement to 20 seconds.

  The measurement result of the sample using the waterproof gas-permeable membrane (waterproof sound-permeable membrane) produced in Example 2 is shown in FIG. 16A. The horizontal axis of FIG. 16A is the frequency (Hz; logarithmic axis) of the sound received by the speaker, and the vertical axis is the elapsed time (seconds) from the start of measurement. The sound pressure level of the sound received by the speaker is represented by the difference in color of the plot shown in FIG. 16A before being expressed in white and black as in the drawing of the present application, that is, in the original state. The relationship between the sound pressure level value and the color is shown on the right side of FIG. 16A. In FIG. 16A, a plurality of curved plots are displayed. The leftmost plot corresponds to the sound (fundamental wave) that is input to the sample from the speaker, passes through the membrane as it is, and is received by the microphone. ing. The plot is curved because the horizontal axis is a logarithmic axis. The plurality of plots seen on the right side of the fundamental wave correspond to a sound having a higher frequency than the fundamental wave that is generated while the fundamental wave passes through the membrane. The sound (input wave) input to the sample changes only to 2 kHz within 20 seconds after starting from 100 Hz, but measurement is started even in the high frequency range of 5 kHz to 20 kHz, which is considered to correlate with the occurrence of chattering sound. It can be seen from FIG. 16A that sound has been detected for approximately 5-12 seconds.

  In the sample using the membrane of Example 2, the ratio A between the integrated sound pressure level A in the sound range of frequencies from 100 Hz to 20 kHz and the integrated sound pressure level B in the sound range of frequencies from 5 kHz to 20 kHz obtained from this FFT analysis / B was 1.28. The cumulative sound pressure level B decreases, that is, the ratio A / B increases, when the sound is less generated in the frequency range of 5 kHz to 20 kHz. For this reason, when the ratio A / B is large, the generation of chatter noise when sound passes through the waterproof sound-permeable membrane is small, that is, the waterproof sound-permeable membrane generates less chatter sound.

  In addition, in the sample using the film of Example 2, a sound pressure level of 40 dB or higher is observed in a sound range of 5 kHz to 20 kHz, and the frequency range of the input wave is 0.7 kHz (minimum frequency 500 Hz, maximum frequency 1 0.2 kHz).

  The measurement result of the sample using the waterproof gas-permeable membrane (waterproof sound-permeable membrane) produced in Comparative Example 2 is shown in FIG. 16B. FIG. 16B and subsequent FIGS. 16C and D are diagrams showing measurement results in the same manner as FIG. 16A. As shown in FIG. 16B, the frequency of the input wave to the sample changes only up to 2 kHz in 20 seconds after starting from 100 Hz, but even in the sound range of 5 kHz to 20 kHz, which is considered to correlate with the generation of chattering sound. Sound was detected for approximately 2-16 seconds from the start of measurement.

  In the sample using the membrane of Comparative Example 2, the ratio A between the integrated sound pressure level A in the sound range of frequencies from 100 Hz to 20 kHz and the integrated sound pressure level B in the sound range of frequencies from 5 kHz to 20 kHz obtained from this FFT analysis / B was 1.15. In the sample using the film of Comparative Example 2, a sound pressure level of 40 dB or higher is observed in the sound range of 5 kHz to 20 kHz, and the frequency range of the input wave is 1.4 kHz (minimum frequency 200 Hz, maximum frequency 1 .6 kHz).

  The measurement result of the sample using the waterproof gas-permeable membrane (waterproof sound-permeable membrane) produced in Example 3 is shown in FIG. 16C. As shown in FIG. 16C, the frequency of the input wave to the sample changes only up to 2 kHz in 20 seconds after starting from 100 Hz, but also in a frequency range of 5 kHz to 20 kHz, which is considered to correlate with the occurrence of chatter noise. Sound was detected for approximately 6-11 seconds from the start of measurement.

  In the sample using the membrane of Example 3, the ratio A between the integrated sound pressure level A in the sound range of frequency 100 Hz to 20 kHz and the integrated sound pressure level B in the sound frequency range of 5 kHz to 20 kHz obtained from this FFT analysis. / B was 1.41. Further, in the sample using the film of Example 3, a sound pressure level of 40 dB or higher is observed in the sound range of the frequency of 5 kHz to 20 kHz. The frequency range of the input wave is 0.5 kHz (minimum frequency 600 Hz, maximum frequency 1 0.1 kHz).

  The measurement result of the sample using the waterproof gas-permeable membrane (waterproof sound-permeable membrane) produced in Example 4 is shown in FIG. 16D. As shown in FIG. 16D, the frequency of the input wave to the sample changes only up to 2 kHz in 20 seconds after starting from 100 Hz, but even in the sound range of 5 kHz to 20 kHz, which is considered to correlate with the generation of chattering sound. Sound was detected for approximately 8-10 seconds from the start of measurement.

  In the sample using the membrane of Example 4, the ratio A between the integrated sound pressure level A in the sound range of frequency 100 Hz to 20 kHz and the integrated sound pressure level B in the sound frequency range of 5 kHz to 20 kHz obtained from this FFT analysis. / B was 1.89. Further, in the sample using the film of Example 4, a sound pressure level of 40 dB or higher is observed in a sound range of 5 kHz to 20 kHz, and the frequency range of the input wave is 0.2 kHz (minimum frequency 800 Hz, maximum frequency 1 0.0 kHz).

  The results of the FFT analysis are summarized in Table 2 below.

The disclosure of this specification includes forms shown in the following items. This invention is not limited to the form shown below.

1. A non-porous resin film in which a plurality of through holes penetrating in the thickness direction are formed;
A liquid repellent layer having openings at positions corresponding to the plurality of through-holes formed on the main surface of the resin film,
The through hole extends linearly and has a diameter of 15 μm or less,
The hole density of the through holes in the resin film is 1 × 10 ³ pieces / cm ² or more and 1 × 10 ⁹ pieces / cm ² or less,
The resin film has the through-hole extending in a direction inclined with respect to a direction perpendicular to the main surface of the film, and the resin film includes the through-holes having different directions extending in an inclined manner. Breathable membrane.

2. The waterproof breathable membrane according to item 1, wherein an angle formed by the inclined and extending direction with respect to the vertical direction is 45 ° or less.

3. The waterproof breathable membrane according to item 1, wherein an angle formed by the inclined and extending direction with respect to the vertical direction is 30 ° or less.

4). Item 1-3, wherein the resin film has a set of through-holes extending in different directions from the main surface at an angle of 90 ° or more when viewed from a direction perpendicular to the main surface of the film. The waterproof breathable membrane according to any one of the above.

5. Item 5. The waterproof breathable membrane according to any one of items 1 to 4, wherein the resin film has the through holes that intersect with each other in the film.

6). The waterproof gas-permeable membrane according to any one of Items 1 to 5, wherein the resin film further includes the through-hole extending in a direction perpendicular to a main surface of the film.

7). The waterproof gas-permeable membrane according to any one of items 1 to 6, wherein the porosity is 50% or less.

8). Item 1 having an air permeability in the thickness direction of 0.01 cm ³ / (cm ² · sec) or more and 100 cm ³ / (cm ² · sec) or less, expressed in terms of the number of fragiles measured according to JIS L1096. The waterproof breathable membrane according to any one of -7.

9. The waterproof gas-permeable membrane according to any one of Items 1 to 8, wherein the waterproof pressure measured in accordance with JIS L1092 water resistance test B method (high water pressure method) is 2 kPa or more.

10. Item 10. The waterproof breathable membrane according to any one of items 1 to 9, wherein the resin film is made of a resin that can be etched with an alkaline solution or an oxidizing agent solution.

11. Item 11. The waterproof breathable membrane according to any one of Items 1 to 10, wherein the resin film is composed of at least one resin selected from polyethylene terephthalate, polycarbonate, polyimide, polyethylene naphthalate, and polyvinylidene fluoride.

12 Item 12. The waterproof breathable membrane according to any one of items 1 to 11, wherein a coloring treatment for absorbing light contained in a wavelength range of 380 nm to 500 nm is applied.

13. 12. The waterproof breathable membrane according to any one of items 1 to 11, which is colored black, gray, brown or pink.

14 14. The waterproof breathable membrane according to any one of items 1 to 13, further comprising a breathable support material laminated on the resin film.

15. The waterproof breathable membrane according to any one of items 1 to 14,
A waterproof ventilation member comprising: a support joined to the waterproof ventilation membrane.

16. A housing having an opening;
A waterproof breathable membrane disposed so as to close the opening and preventing water from entering the inside through the opening while allowing gas to pass between the inside and outside of the housing;
The waterproof ventilation structure, wherein the waterproof ventilation film is the waterproof ventilation film according to any one of Items 1 to 14.

17. A housing having an opening;
A waterproof breathable membrane disposed so as to close the opening and preventing water from entering the inside through the opening while allowing gas to pass between the inside and outside of the housing;
The electronic device in which the waterproof gas-permeable membrane is the waterproof gas-permeable membrane according to any one of Items 1 to 14.

18. An electronic device case that houses an electronic device,
Has an opening,
The waterproof breathable membrane is disposed so as to close the opening, and prevents gas from entering from the outside through the opening while allowing gas to pass between the inside and the outside of the case,
The case for electronic devices in which the waterproof gas-permeable membrane is the waterproof gas-permeable membrane according to any one of Items 1 to 14.

19. A non-porous resin film in which a plurality of through holes penetrating in the thickness direction are formed;
A liquid repellent layer having openings at positions corresponding to the plurality of through-holes formed on the main surface of the resin film,
The through hole extends linearly and has a diameter of 15 μm or less,
The hole density of the through holes in the resin film is 1 × 10 ³ pieces / cm ² or more and 1 × 10 ⁹ pieces / cm ² or less,
The resin film has the through-hole extending in a direction inclined with respect to a direction perpendicular to the main surface of the film, and the resin film includes the through-holes having different directions extending in an inclined manner. Sound-permeable membrane.

20. Item 20. The waterproof sound-permeable membrane according to Item 19, wherein an angle formed by the inclined and extending direction with respect to the vertical direction is 45 ° or less.

21. Item 20. The waterproof sound-permeable membrane according to Item 19, wherein an angle formed by the inclined and extending direction with respect to the vertical direction is 30 ° or less.

22. The items 19 to 21, wherein the resin film has the set of through holes that extend in different directions from the main surface at an angle of 90 ° or more when viewed from a direction perpendicular to the main surface of the film. The waterproof sound-permeable membrane according to any one of the above.

23. 23. The waterproof sound-permeable membrane according to any one of items 19 to 22, wherein the resin film has the through holes that intersect with each other in the film.

24. 24. The waterproof sound-permeable membrane according to any one of items 19 to 23, wherein the resin film further has the through-hole extending in a direction perpendicular to the main surface of the film.

25. The waterproof sound-permeable membrane according to any of items 19 to 24, wherein the porosity is 50% or less.

26. Item 19 having an air permeability in the thickness direction of 0.01 cm ³ / (cm ² · sec) or more and 100 cm ³ / (cm ² · sec) or less, indicated by the number of fragiles measured in accordance with JIS L1096. The waterproof sound-permeable membrane as described in any one of -25.

27. 27. The waterproof sound-permeable membrane according to any one of items 19 to 26, wherein the water pressure measured in accordance with JIS L1092 water resistance test B method (high water pressure method) is 2 kPa or more.

28. 28. The waterproof sound-permeable membrane according to any of items 19 to 27, wherein the resin film is made of a resin that can be etched with an alkali solution or an oxidant solution.

29. 29. The waterproof sound-permeable membrane according to any of items 19 to 28, wherein the resin film is composed of at least one resin selected from polyethylene terephthalate, polycarbonate, polyimide, polyethylene naphthalate, and polyvinylidene fluoride.

30. 30. The waterproof sound-permeable membrane according to any one of items 19 to 29, wherein a coloring treatment for absorbing light included in a wavelength range of 380 nm to 500 nm is performed.

31. 30. The waterproof sound-permeable membrane according to any one of items 19 to 29, which is colored black, gray, brown, or pink.

32. 32. The waterproof sound-permeable membrane according to any one of items 19 to 31, further comprising a breathable support material laminated on the resin film.

33. 33. The waterproof sound-permeable membrane according to any one of items 19 to 32,
An input sound having a sine wave waveform and maintaining a sound pressure level such that the sound pressure level of a sound having a frequency of 1 kHz after passing through the film is 94 dB starts from 100 Hz at a rate of 100 Hz / second. When inputting to the membrane with an effective area of 132.7 mm ² while continuously increasing the frequency,
The integrated sound pressure level A in the frequency range of 100 Hz to 20 kHz, and the frequency of 5 kHz to 20 kHz, obtained by FFT analysis for the sound that has passed through the membrane until 20 seconds have passed since the start of input of the input sound. A waterproof sound-permeable membrane having a ratio A / B to an integrated sound pressure level B in the sound range of 1.16 or more.

34. The waterproof sound-permeable membrane according to any one of items 19 to 33,
An input sound having a sine wave waveform and maintaining a sound pressure level such that the sound pressure level of a sound having a frequency of 1 kHz after passing through the film is 94 dB starts from 100 Hz at a rate of 100 Hz / second. When inputting to the membrane with an effective area of 132.7 mm ² while continuously increasing the frequency,
A sound pressure level of 40 dB or more is observed in a sound range of a frequency of 5 kHz or more and 20 kHz or less with respect to a sound that has passed through the membrane until 20 seconds have passed after the input sound is input, and the frequency range of the input sound is 1 A waterproof sound-permeable membrane that is 3 kHz or less.

35. The waterproof sound-permeable membrane according to any one of items 19 to 34,
An input sound having a sine wave waveform and maintaining a sound pressure level such that the sound pressure level of a sound having a frequency of 1 kHz after passing through the film is 94 dB starts from 100 Hz at a rate of 100 Hz / second. When inputting to the membrane with an effective area of 132.7 mm ² while continuously increasing the frequency,
A sound pressure level of 40 dB or higher is observed in a sound range of 5 kHz or more and 20 kHz or less with respect to the sound that has passed through the membrane until 20 seconds have passed after the input of the input sound is started. The maximum frequency of the input sound is 1. A waterproof sound-permeable membrane that is 5 kHz or less.

36. The waterproof sound-permeable membrane according to any one of items 19 to 35,
A waterproof sound-permeable member comprising a support joined to the waterproof sound-permeable film.

37. A housing provided with an opening for transmitting sound between the inside and the outside;
A waterproof sound-permeable membrane disposed so as to close the opening, and transmitting sound between the inside and the outside and preventing water from entering the inside through the opening from the outside,
The waterproof sound-permeable structure, wherein the waterproof sound-permeable film is the waterproof sound-permeable film according to any one of Items 19 to 35.

38. A housing in which an acoustic unit is accommodated and an opening for transmitting sound between the acoustic unit and the outside is provided;
A waterproof sound-permeable membrane disposed so as to close the opening and transmitting sound between the acoustic unit and the outside and preventing water from entering the housing from the outside through the opening; ,
The electronic device, wherein the waterproof sound-permeable membrane is the waterproof sound-permeable membrane according to any one of Items 19 to 35.

39. An electronic device case for housing an electronic device having an acoustic part,
An opening for transmitting sound between the acoustic part of the electronic device and the outside is provided,
A waterproof sound-permeable membrane disposed so as to close the opening and transmitting sound between the acoustic part of the electronic device and the outside and preventing water from entering the case from the outside through the opening Prepared,
The case for electronic devices, wherein the waterproof sound-permeable membrane is the waterproof sound-permeable membrane according to any one of Items 19 to 35.

  The waterproof breathable membrane of the present invention can be used for the same applications as conventional waterproof breathable membranes. The waterproof sound-permeable membrane of the present invention can be used for the same applications as conventional waterproof sound-permeable membranes.

DESCRIPTION OF SYMBOLS 1 Waterproof breathable film 2 Resin film 21,21a-q Through-hole 22 (22a, 22b) Opening of (through-hole 21) 23 Through-hole 3 Liquid repellent layer 31 Opening 32 Original film 33 Sending roll 34 Irradiation roll 35 Winding roll 36 Ion beam 4 Breathable support layer 5 Waterproof breathable member 51 (Waterproof breathable member) support 6 Smartphone (electronic device)
61 Housing 62a, 62b, 62c Opening 7 Electronic device case 71a, 71b, 71c Opening 72 (inside the electronic device case) 73 Film 8 Waterproof ventilation structure 81 Housing 82 Opening 83 (in housing 81) Inside 91 Simulated Case 92 Speaker mounting hole 93 Conduction port 95 Speaker 96 Speaker cable 97 Microphone

Claims (20)

A non-porous resin film in which a plurality of through holes penetrating in the thickness direction are formed;
A liquid repellent layer having openings at positions corresponding to the plurality of through-holes formed on the main surface of the resin film,
The through hole extends linearly and has a diameter of 15 μm or less,
The hole density of the through holes in the resin film is 1 × 10 ³ pieces / cm ² or more and 1 × 10 ⁹ pieces / cm ² or less,
The resin film has the through-hole extending in a direction inclined with respect to a direction perpendicular to the main surface of the film, and the resin film includes the through-holes having different directions extending in an inclined manner. Breathable membrane.   The waterproof breathable membrane according to claim 1, wherein an angle formed by the inclined and extending direction with respect to the vertical direction is 45 ° or less.   The waterproof breathable membrane according to claim 1, wherein an angle formed by the inclined and extending direction with respect to the vertical direction is 30 ° or less.   The said resin film has the said through-hole group which extends in the mutually different direction from the said main surface at an angle of 90 degrees or more, seeing from the direction perpendicular | vertical to the main surface of the said film. The waterproof breathable membrane according to any one of the above.   The waterproof gas-permeable membrane according to any one of claims 1 to 4, wherein the resin film has the through holes that intersect with each other in the film.   The waterproof breathable membrane according to any one of claims 1 to 5, wherein the resin film further has the through hole extending in a direction perpendicular to a main surface of the film.   The waterproof breathable membrane according to any one of claims 1 to 6, wherein the porosity is 50% or less. The air permeability in the thickness direction is 0.01 cm ³ / (cm ² · sec) or more and 100 cm ³ / (cm ² · sec) or less in terms of fragile number measured according to JIS L1096. The waterproof breathable membrane according to any one of 1 to 7.   The waterproof breathable membrane according to any one of claims 1 to 8, wherein the waterproof pressure measured in accordance with JIS L1092 water resistance test B method (high water pressure method) is 2 kPa or more.   The waterproof breathable membrane according to any one of claims 1 to 9, wherein the resin film is made of a resin that can be etched with an alkali solution or an oxidant solution.   The waterproof breathable membrane according to any one of claims 1 to 10, wherein the resin film is composed of at least one resin selected from polyethylene terephthalate, polycarbonate, polyimide, polyethylene naphthalate, and polyvinylidene fluoride.   The waterproof breathable membrane according to any one of claims 1 to 11, wherein a coloring treatment for absorbing light contained in a wavelength range of 380 nm to 500 nm is applied.   The waterproof gas-permeable membrane according to any one of claims 1 to 11, which is colored black, gray, brown or pink.   The waterproof breathable membrane according to any one of claims 1 to 13, further comprising a breathable support member laminated on the resin film. The waterproof breathable membrane according to any one of claims 1 to 14,
A waterproof ventilation member comprising: a support joined to the waterproof ventilation membrane. A housing having an opening;
A waterproof breathable membrane disposed so as to close the opening and preventing water from entering the inside through the opening while allowing gas to pass between the inside and outside of the housing;
The waterproof ventilation structure whose said waterproof ventilation film is the waterproof ventilation film in any one of Claims 1-14. A non-porous resin film in which a plurality of through holes penetrating in the thickness direction are formed;
A liquid repellent layer having openings at positions corresponding to the plurality of through-holes formed on the main surface of the resin film,
The through hole extends linearly and has a diameter of 15 μm or less,
The hole density of the through holes in the resin film is 1 × 10 ³ pieces / cm ² or more and 1 × 10 ⁹ pieces / cm ² or less,
The resin film has the through-hole extending in a direction inclined with respect to a direction perpendicular to the main surface of the film, and the resin film includes the through-holes having different directions extending in an inclined manner. Sound-permeable membrane. The waterproof sound-permeable membrane according to claim 17,
An input sound having a sine wave waveform and maintaining a sound pressure level such that the sound pressure level of a sound having a frequency of 1 kHz after passing through the film is 94 dB starts from 100 Hz at a rate of 100 Hz / second. When inputting to the membrane with an effective area of 132.7 mm ² while continuously increasing the frequency,
The integrated sound pressure level A in the frequency range of 100 Hz to 20 kHz, and the frequency of 5 kHz to 20 kHz, obtained by FFT analysis for the sound that has passed through the membrane until 20 seconds have passed since the start of input of the input sound. A waterproof sound-permeable membrane having a ratio A / B to an integrated sound pressure level B in the sound range of 1.16 or more. The waterproof sound-permeable membrane according to claim 17 or 18,
An input sound having a sine wave waveform and maintaining a sound pressure level such that the sound pressure level of a sound having a frequency of 1 kHz after passing through the film is 94 dB starts from 100 Hz at a rate of 100 Hz / second. When inputting to the membrane with an effective area of 132.7 mm ² while continuously increasing the frequency,
A sound pressure level of 40 dB or more is observed in a sound range of a frequency of 5 kHz or more and 20 kHz or less with respect to a sound that has passed through the membrane until 20 seconds have passed after the input sound is input, and the frequency range of the input sound is 1 A waterproof sound-permeable membrane that is 3 kHz or less. The waterproof sound-permeable membrane according to any one of claims 17 to 19,
An input sound having a sine wave waveform and maintaining a sound pressure level such that the sound pressure level of a sound having a frequency of 1 kHz after passing through the film is 94 dB starts from 100 Hz at a rate of 100 Hz / second. When inputting to the membrane with an effective area of 132.7 mm ² while continuously increasing the frequency,
A sound pressure level of 40 dB or higher is observed in a sound range of 5 kHz or more and 20 kHz or less with respect to the sound that has passed through the membrane until 20 seconds have passed after the input of the input sound is started. The maximum frequency of the input sound is 1. A waterproof sound-permeable membrane that is 5 kHz or less.